The present invention relates to an image information registering/retrieving system, and more particularly to an image information registering/retrieving system of the type in which a plurality of image information on documents is successively registered on an optical disk and a plurality of retrieving data corresponding to the image information is stored on a magnetic disk, and any desired image information is read out using a retrieving data associated with the desired image information.
In an image information registering/retrieving system which is known and practically used, a plurality of image information is obtained by optically scanning documents and registering on an optical disk. A plurality of retrieving data for retrieving the image information is stored on a magnetic disk. A control unit controls the optical disk and the magnetic disk. Selected retrieving data in the magnetic disk is read out and applied to the control unit. Using the selected retrieving data, the control unit specifies that location of the optical disk on which the desired information is registered, and reads out the desired image information thereform. The read-out image information is visualized by a CRT display or recorded by a recording device.
The image information registering/retrieving system having the above described functions requires a magnetic memory device for driving the magnetic disk. When used for a long time, the magnetic disk wears down and possibly loses its function. In such a case, it is not possible to read out the retrieving data therefrom, resulting in that the functions of the image information registering/retrieving system per se stop. To cope with this, the prior system is provided with an auxiliary magnetic memory device. This leads to an increase in the cost of manufacture, however. To avoid the increased cost, the magnetic memory device may be designed such that the defective magnetic disk is replaced with a new disk. This approach indeed succeeds in restricting the increase of cost to some degree. Nevertheless, it takes a long time to store the retrieving data onto the new magnetic disk. In this respect, this approach is not practical. A more serious disadvantage of the approach is that it is very difficult to keep the predetermined correspondence between the retrieving data on the magnetic disk and the image information registered in the optical disk.